Building Your Own IrDA Interface?

agdv ponders a cool sounding project: "I am interested in giving my desktop PC IrDA capabilities, as it has an IrDA header in its motherboard. While not very useful for my current needs, it would allow me to play some and have it ready should I ever need to transfer stuff to it from say a PDA. I know I can get one for about 25 bucks from eBay, but I was wondering if it could be reasonably easy to make one myself."

"I know it would be way more fun, possibly cheaper, and I presume I can get all the necessary materials from RadioShack or Mouser (I made a cable for direct serial connection and one for connecting my TI computer to my PC that way, but I don't know if this would be a bit out of my league). Has anybody tried something like that? Is it feasible? Do you have instructions, or hardware to reverse-engineer?"

If only more PC makers would make this a standard port, IR would be very useful. As it is ... does anyone have any successful projects to reveal?